The subject matter disclosed herein relates to a multi-pressure organic Rankine cycle using a dry organic working fluid.
Waste heat recovery systems may be employed to recover low-grade heat from industrial and commercial processes and operations. For example, waste heat recovery systems may be used to recover low-grade heat from hot exhaust gases produced by gas turbines. Waste heat recovery systems that implement an organic Rankine cycle (ORC) with an organic working fluid may be particularly efficient at recovering low-grade heat due to the relatively low phase change enthalpies of organic fluids.
Additionally, ORC systems can be utilized in geothermal power plants. Geothermal power plants seek to utilize natural reservoirs of steam and hot water (e.g., brine) to generate electricity. The steam and hot water from geothermal reservoirs is generally obtained at low-grade temperatures, and thus, an ORC system may be an efficient method for generating electricity using a geothermal reservoir heat source.
Traditional ORCs tend to be less efficient when the temperature of the heat source decreases. Therefore, a modified ORC system that can generate electricity using low-grade heat sources more efficiently is desired.